Can we prove that God Exists?Philosophers through the centuries have tried to prove whether God exists

Does God exist?Discuss in your groups.

Nearly everyone who has ever lived and currently 85% of the worlds population believe that God exists. They may disagree as to the details of this belief, but they believe nonetheless.

Over the next few weeks we will be exploring the different reasons people have given for believing in God

This lesson will be successful if:You can explain the terms deductive and

inductive, analytic and synthetic, in intellectu and in re

You can outline Anselm’s first ontological argument for the existence of God

How would you prove the truth of each of these statements?Father Christmas has a red coatUnicorns are whiteAdolf Hitler’s actions were evilGod existsMurder is wrongTwo plus two equals fourThe prime minister is mortal

Consider the following statements:Which are

a)Trueb)Need to be proven with evidence

1)A triangle has three internal angles which add up to 180 degrees

2)Yetis walk in the Himalayas3)Unicorns are white and have a horn on their head

Analytic StatementsA statement that is ridiculous and

impossible to think of as false:‘An analytic or logically necessary proposition is

one which it would be incoherent to suppose to be false; ‘all squares have four sides’ and ‘red is a colour’ are logically necessary, because it would be incoherent, make no sense to suppose that red could be anything except from a colour, or that a square could have anything other than three sides.’ Swinburne, The existence of God

Some philosophers say that we can prove God exists by analysing the and can be known a: The Ontological Argument

The Ontological Argument

Works by analysing the concept of God. We must discover all the ideas that are bundled together within the concept – for example:

Unpack the following ideasBachelorBrotherUnicorn

St Anselm of Canterbury1033 – 1109Born in Piedmont, ItalyBecame Archbishop of Canterbury in 1093Wrote many books examining the nature of

God and the relationship between the Church and State in medieval Europe. He was influenced by Plato.

St Anselm (1033-1109) First version of the ontological argument (Proslogion):

1) God is “that than which nothing greater can be conceived”

2) Even a fool (someone who doesn’t believe in God) can understand that God is the greatest conceivable being

3) (From Psalm 14 and 53) The fool says there is no God in reality

4) (From 2 and 3) The fool is convinced that God, the greatest possible being exists only in his understanding and not in reality

.

5) It is greater to exist in understanding and reality, than merely in the understanding.

6) (From 5) The greatest conceivable being, if it is genuinely the greatest, must exist in understanding and reality

7) (Conclusion from 1 and 6) Therefore God exists in both reality and in understanding. Moreover (from 4 and 6) the fool is really a fool as he is denying the existence of the greatest possible being, ie: a being which must exist if it is genuinely the greatest.

Anselm Says: Something that really exists (in re) is bound to be greater than something that just existed in thought (in intellectu)

Which is more perfect?Would you prefer……

Anselm simplified1) God is the greatest conceivable being2) It is greater to exist in reality (in re)

rather than in understanding alone (in intellectu)

3) Therefore the greatest conceivable being, must exist in the understanding and in reality

SO:God must exist. If we follow the steps, we can deduce that logically, there must be a God.

What problems do you see with this?

Anselm’s Second version (Proslogion 3)1) God is that being nothing greater than which

can be thought of2) Something which cannot be thought not to

exist is greater than anything which can be thought not to exist

3) Therefore it is impossible to think that this being cannot exist

4) And this being is what we call God

Anselm’s second version adds a further point. That it is impossible for this being not to exist. In other words ‘this being’ has to exist. (Necessary)

Furthermore, if you are saying ‘God does not exist’ – according to Anselm, you are contradicting yourself.

Contingence and NecessityAnything that cannot fail to exist has ‘NECESSARY

EXISTENCE’Most things that exist depend on something else for their

existence – this is CONTINGENT EXISTENCE’

Anselm argues Necessary existenceAnselm argues that if God existed only contingently,

then he would depend on something else for his existence and therefore would not be as great as the being who created him!

Descartes says:A triangle has necessary properties

God has necessary properties

Descartes (and Anselm) claims it is a deductive argument:The Premises reach a logical conclusion:

If the premises are true, the conclusion must be true:

Premise 1: A triangle has three sidesPremise 2: This shape has three sidesConclusion: Therefore it is a triangle

But not all deductive arguments work :A valid argument is one where there is no mistakes in

the logic

Premise 1: The Eiffel Tower is in ParisPremise 2: Paris is in France Conclusion: Therefore, the Eiffel Tower is in France

Premise 1: The Eiffel Tower is in WorthingPremise 2: Worthing is in EnglandConclusion: Therefore, the Eiffel Tower is in England

Now make your own valid deductive argument and an invalid deductive argument

Descartes says:Premise 1: God has every perfectionPremise 2: Existence is a perfectionConclusion: God must exist

Is there a problem with this logic?

‘It’s all a matter of deduction, Dear Watson.’

http://www.youtube.com/watch?v=PVLcDTD5gU8

Deductive/Inductive arguments:Complete the Deductive/Inductive question

sheet

GauniloWas a compatriot of Anselm.He was a Benedictine Monk

He criticised Anselm in 3 ways entitled ‘On Behalf of a Fool’

1) GossipThe fool could have in mind all sorts of

things that do not exist in reality. Gaunilo uses the example of someone hearing about a person from gossip. Gossip is unreliable.

2) Defining things into existenceYou cannot demonstrate the existence of

something by having an idea of it. Gaunilo uses the medieval idea that you cannot prove from what is said (de dicto) to what exists in reality (de re)

Draw your Perfect IslandYou have 7 minutes

3) Gaunilo’s ArgumentThis argument implies that it is absurd to say

that something exists just because you have an idea of it.

Gaunilo concludes that Anselm cannot demonstrate or prove that the idea of God as the greatest possible being means that God exists in reality.

Anselm responds to Gaunilo1) God is the greatest possible being - his existence is

NECESSARY. Gaunilo’s argument is different – an island does not have to exist – it is CONTINGENT.

2) Anselm argues that if you conceive of the greatest possible being, you cannot think of a being that cannot be conceived as not existing. This is not the same for an island – it can NOT exist.

3) Alvin Plantinga says that Anselm could say: ‘however great the Island, there could always be one better – there is no ‘intrinsic maximum’.

Complete the Inductive/Deductive argument sheetLet’s go through the sheet together.

Key Words Wordle

Key Words Dominoes

Make dominoes for the key words that we have learned in this unit and give them to another pair

Thomas Aquinas rejects AnselmHuman’s cannot know or

understand God’s greatness. We cannot KNOW that God exists is an analytic statement.

We MUST prove that God exists using a synthetic argument (he says use the Cosmological or Teleological argument to prove God’s existence.)

Descartes’ Ontological ArgumentHis argument was formed in his Meditations. He began by defining God as ‘a supremely perfect being’From this definition he tried to prove Gods existence.•Because of he is a supremely perfect being then his has all perfections•So being perfect means existing•Therefore God exists

Descartes argued that God exists in the same way that a triangle must have 3 sides and 3 angles that add up to 180

This argument can only apply to something that is perfect.

Comparing the ArgumentsSimilarities

Both philosophers aimed to prove that God did exist.

Both state that God is perfect and that nothing else can be of greater perfection.

They both establish Gods existence as being necessary.

Differences Anselm starts with the notion of

God as a being of which no greater can be conceived, while Descartes starts with the notion of God as being totally perfect.

The AtheistNeedless to say, for the atheist, this argument is futile, since the fact that atheism can be held as a rationally consistent position (i.e. it is equally possible to experience the world consistently as an atheist or as a theist) means that the non existence of God can be conceived as rationally certain.

Kant – existence is not a predicate

Kant believed that existence does not add anything to the qualities of God.

Bertrand RussellRussell proposed that the two claims 'Cows exist' and 'Unicorns do not exist' do not say that they have or do not have a particular attribute of existence. Rather, we use them to say that one has an instance (cows) and one does not (unicorns).Unicorns exist only in the mind, Cows exist in reality. You cannot say that unicorns exist just because they exist in intellectu.

Bertrand RussellRussell had, as a young man, been almost convinced that the argument worked:'I remember the precise moment, one day in 1894, as I was walking along Trinity Lane, when I saw in a flash (or thought I saw) that the ontological argument is valid. I had gone out to buy a tin of tobacco; on the way back, I suddenly threw it up in the air, and exclaimed as I caught it: 'Great Scott, the ontological argument is sound'(The God Delusion, Bantam Press, 2006).

Hume and Kant'Both Hume and Kant showed that it is not possible to move from the de dicto necessity of a proposition to the de re necessity of God ... They also challenged the very idea of anything being necessary, maintaining that the only things that are necessary are linguistic statements where truth represents convention (for instance, de dicto necessary statements such as 'all triangles have three angles')'

(Peter Vardy, What is Truth?, University of New South Wales Press, 1999).

Ontological Argument

Using a spider diagram, or other useful format, summaries the contributors to the ontological argument and what they contributed.

Ontological Argument

Ontological Argument

What are the key objections to the Ontological Argument?Which do you think is the most effective and why?

Explain the ontological argument from Anselm and Gaunilo’s objections to it. (25)

The Ontological argument is a convincing argument. Discuss. (10)

(a) Explain the Ontological Argument from Anselm and Gaunilo’s objection to it (25)(b) ‘The Ontological Argument is a convincing argument’. Discuss. (10)

By email by 11th November…